For those of us going back to school after some time in the workforce, I would keep in mind that if you convert your 401(k) to an IRA, you can use the funds to pay for tuition, books, supplies, and living expenses (including rent, if you are a full time student), without paying a penalty. You will still have to pay income tax on the distributions, but since taxable income will likely be low while you are in school, that should be relatively minimal.
This is obviously not what I was hoping to use my retirement savings for as I have put it away over the past few years, but to me, this is preferable to going into massive debt to pay for school. Will have time to build it back up over the years...